Implantable medical device for improved placement and adherence in the body

ABSTRACT

A medical device comprises a flexible member that can be adhesively attached to a housing of the medical device, allowing implantation of the medical device into a body through an incision of reduced size. The flexible member can be attached to the housing either before or after implantation into the body. The flexible member comprises suture locations, including a permeable membrane or a suture hole, for suturing the medical device to tissue of the body. The suture holes can be filled with a substance penetrable by a suture needle, to minimize tissue ingrowth before or after suturing.

FIELD OF THE INVENTION

[0001] This invention relates generally to implanted medical devicesused to access subcutaneous regions within a body, such as vasculature.

BACKGROUND OF THE INVENTION

[0002] Long term access to a patient's body is required for many medicaltreatments including antibiotic therapy, hemodialysis access,chemotherapy regimens, and other treatments that require repeatedadministration, withdrawal, or exchange of fluids. In some cases,internal access to the patient is required for years.

[0003] Subcutaneously implanted access ports are one type of medicaldevice that can be used for this purpose. These medical devices ofteneither include or are attached to a catheter used for theadministration, withdrawal, and/or exchange of fluids from the patient.A pocket is made in the subcutaneous tissue, and the medical device isplaced into the pocket.

[0004] Access ports generally have a molded or rigid housing, with afixed number of suture holes. These suture holes protrude from thehousing of the medical device, causing it to have a larger overall sizethan it otherwise would have. During implantation, a physician is thusrequired to create an incision in the body of sufficient size to allowinsertion of the device. Further, rigid appendages on the housing of themedical device can make manipulation of the device within the body of apatient difficult for a physician.

[0005] Suturing of such a device can be performed by the physician tosecure or stabilize the device. A number of factors determine whether ornot the medical device is sutured in place, including the pocketconfiguration, the type of training received by the physician, and thephysician's preference. Once the device is properly positioned andsecured, the pocket is closed.

[0006] There is a wide range of preferences among physicians regardingthe number and location of suture holes. Some physicians prefer one,two, three, four, or more suture holes. Some physicians prefer not tohave any suture holes, and yet others prefer to have any suture holesthat are present filled with a material such as silicone to minimizefibrin ingrowth into the suture holes, thereby facilitating subsequentremoval of the device.

[0007] After suturing has been completed, the rigid housing of themedical device and the associated suture holes do not readilyaccommodate movement of the patient. Movement of the patient causes thetissue to which the medical device has been sutured to move. Therigidity of the device thus results in increased tension on the sutures,resulting in discomfort and irritation to the patient.

SUMMARY OF THE INVENTION

[0008] In one aspect, the invention features an implantable medicaldevice for percutaneous access to a body comprising a flexible memberand a housing defining an entry site for the administration, withdrawal,or exchange of fluids. The flexible member is attached to a surface ofthe housing and stabilizes placement of the medical device within thebody. An adhesive is disposed on a first surface of the flexible memberand attaches the flexible member to the housing surface. The flexiblemember can comprise suture locations, and the suture locations candefine one or more suture holes. The suture holes can be filled with amaterial to minimize tissue ingrowth, such as fibrin. The material canbe silicone or a biocompatible polymer, and is preferably penetrable bya suture needle.

[0009] The flexible member can have a perimeter region penetrable by asuture needle, which can be formed of materials including polyurethane,thermoplastics, elastomers, and fiber reinforced elastomers. Theflexible member can also include tabs, which can be located about aperimeter of the flexible member. The tabs can define one or more sutureholes.

[0010] The flexible member can be coated with a tissue growth substanceand can be shaped and/or textured to conform to tissue within the body.A second surface of the flexible member can include an adhesive forattaching the device to tissue within the body. The flexible member canbe preformed to mate with the housing. It can also be shaped to surrounda perimeter of the housing.

[0011] Another aspect of the invention features a flexible member forstabilizing the placement of a medical device within a body. Theflexible member includes a flexible substrate that mates with themedical device, one or more suture locations formed on the flexiblesubstrate, and an adhesive. The flexible member can be formed from amaterial penetrable by a suture needle. Materials such as polyurethanes,thermoplastics, elastomers, and fiber-reinforced elastomers can be usedto form the flexible member.

[0012] The flexible member can comprise one or more suture locations,and these can each define one or more suture holes. The suture holes canbe filled with a tissue growth substance that inhibits tissue growth.The suture holes can be filled with substances such as silicone andbiocompatible polymers. In one embodiment, the substance is penetrableby a suture needle.

[0013] The flexible member can also include tabs, and the tabs can bedisposed about the perimeter of the flexible member. The tabs can beflexible and can be penetrable by a suture needle. The flexible membercan be coated with a substance to inhibit tissue growth. It can also bepreformed to mate with the perimeter of a surface of the medical deviceand can have a second surface shaped to conform to subcutaneous tissuewithin the body.

[0014] At least a portion of the perimeter of the flexible member canfollow a perimeter of the surface of the medical device to which theflexible member is attached. The flexible member can include an adhesiveto secure the flexible member to the medical device. The adhesive caninclude methoxy-perfluoropropane, thixotropic sealants, and water-basedadhesives.

[0015] Another aspect of the invention features a method ofmanufacturing an implantable medical device that comprises providing ahousing defining an entry site for the administration, withdrawal, orexchange of fluids, and attaching a flexible member thereto, forstabilizing placement of the housing within the body. The flexiblemember can be formed by cutting a sheet of polymer. The method caninclude applying an adhesive to the flexible member by at least one ofspray coating, slot coating, spiral spraying, melt-blowing, patterncoating, layering, dipping and drying, and ion deposition.

[0016] Another aspect of the invention features a method of fabricatinga flexible member which includes forming a shape for mating with animplantable medical device, forming suture locations about the shape ofthe flexible member, and applying an adhesive to the shape. The locationbe formed by cutting from a sheet of polymer, and suture holes can beformed in the shape member.

BRIEF DESCRIPTION OF THE DRAWINGS

[0017] These and other features of the invention are more fullydescribed below in the detailed description and accompanying drawings ofwhich the figures illustrate an apparatus and method for securing animplantable medical device within a body.

[0018]FIG. 1 illustrates a prior art device used to provide access toprovide access to subcutaneous regions within a body, such asvasculature.

[0019]FIG. 2 illustrates another prior art device with only one entrysite.

[0020]FIG. 3 illustrates a side elevation view of an embodiment of theinvention.

[0021]FIG. 4 illustrates a side and top view of another embodiment ofthe invention.

[0022] FIGS. 5-8 are a top view of other embodiments of the invention.

[0023]FIGS. 9 and 10 are perspective views that show different ways theflexible member can be attached to a surface of a medical device.

[0024] FIGS. 11-14 are top views illustrating additional embodiments ofthe invention.

[0025]FIG. 15 is a side view of a flexible member shaped to conform totissue within the body.

[0026]FIG. 16 is a side view of a flexible member that is preformed tomate with a medical device.

[0027] FIGS. 17-18 illustrate embodiments of the invention withdifferent thickness characteristics.

[0028]FIGS. 19 and 20 each illustrate an embodiment of the inventionwith different surface textures.

[0029]FIG. 21 is a flow chart illustrating steps that can be used tomanufacture a flexible member of the invention.

[0030]FIG. 22 is a flow chart illustrating steps that can be used by aphysician to prepare the flexible member for use.

[0031]FIG. 23 is a flow chart illustrating steps that can be used toimplant a medical device of the invention.

DETAILED DESCRIPTION

[0032]FIG. 1 shows a prior art access port used by a physician toprovide access to subcutaneous regions within the body, such asvasculature. The medical device 10 includes a housing 11 and an entrysite 12 for the administration, withdrawal, or exchange of fluids. Theentry site can be a septum. The needle of a syringe, for example, can beused to administer or withdraw fluids through the septum. The medicaldevice can be surgically implanted beneath the skin of a patient.

[0033] The medical device can also include a predetermined number ofsuture holes 14 disposed about the base of the housing in fixedlocations. The suture holes can be molded into the housing 11 as shown.A physician can tie a suture through the suture hole, thus securing themedical device 10, for example, to adjacent tissue. The medical deviceshown has two entry sites 12.

[0034]FIG. 2 illustrates another prior art access port with a singleentry site 12. A catheter 22 is attached to the medical device 10.Suture holes 14 are disposed about the base of the housing 11 at fixedlocations.

[0035]FIG. 3 is an illustration of an embodiment of an access portincorporating principles of the invention. The medical device 10comprises housing 11 and an entry site 12. The shape of the housing 11defines the entry site 12, as shown. The entry site is used toadminister, withdraw, or exchange fluids with a body, and can comprise aseptum. A physician can penetrate the septum with the needle of asyringe.

[0036] A flexible member 30 is attached to a surface 32 of the housing.A perimeter region 35 of the member 30 is non-rigid and flexible. Whenflexed, the size of the incision required for insertion of the medicaldevice in a body can be reduced. Suture locations 38 are disposed alongthe perimeter region 35 of the flexible member 30.

[0037]FIG. 4 illustrates a flexible member 30 having a first surface 41and a second surface 44. The first surface 41 comprises an adhesive,which allows the flexible member to be attached to the surface of thehousing 32. In one embodiment, the flexible member is preformed tape,having an adhesive surface that easily adheres to the surface of thehousing 32. The tape can take various shapes, forms, thicknesses, andorientations. The flexible member 30 can be attached to the housingsurface 32 before surgery. Adhesively attaching the flexible member 30to housing surface 32 of medical device 10 allows a physician to implantthe medical device within a body using an incision of reduced size.Alternatively, the flexible member can be attached to the housingsurface after implantation into a body. This is accomplished byattaching the flexible member 30 to the housing 32 after each has beeninserted into the body through the incision. In this embodiment, theincision size can be reduced still further.

[0038] The flexibility of the member 30 also enhances the manipulationand placement attributes of the device, providing a physician withincreased capabilities and reducing aggravation and irritation to apatient. Patient recovery and comfort are thus enhanced. The flexiblemember also results in improved comfort and reduced irritation to thepatient after the medical device has been implanted. Movement of apatient causes the tissue to which the medical device has been suturedto move. The resiliency of the flexible member thus reduces the stressto the body tissues of the patient during movement of the patient. Thisresults in reduced irritation to the body and increased patient comfort.If sutures are present (discussed below), the benefit of this feature isincreased.

[0039] The perimeter region 35 of the flexible member 30 can extendbeyond the perimeter 47 of the housing surface. As shown, the perimeterregion 35 of the flexible member 30 can extend beyond the perimeter ofthe housing surface 47 on all sides. In other embodiments, the perimeterregion 35 can extend beyond the perimeter 47 of the housing surface onfewer than all sides.

[0040] FIGS. 5-8 show a top view of different embodiments of theinvention. FIGS. 5 and 6 illustrate a flexible member comprising aperimeter region 35. This perimeter region 35 can extend beyond theperimeter of the housing surface 47 when the flexible member is attachedto surface 32 of housing 11. The perimeter region 35 can extend beyondthe housing perimeter 47 in all directions, as shown. In otherembodiments, it extends beyond the housing perimeter 47 in fewerdirections. In any of these embodiments, a plurality of suture locations38 can be disposed about the perimeter region 35 of the flexible member30.

[0041]FIGS. 7 and 8 illustrate flexible members 30 comprising preformedtabs 72 that extend beyond the perimeter of the housing surface 47. Eachof these tabs 72 can include one or more suture locations 38.

[0042] Each of the embodiments found in FIGS. 5-8 can be formed as apreformed flexible member. The shapes illustrated in these figures areintended to conform generally to the perimeter of the housing surface 47to which they can be attached. In other embodiments, however, theflexible member may not conform to the perimeter of the housing.

[0043]FIG. 9 illustrates the manner in which an embodiment of theflexible member 91 can be joined with the housing surface 32A of medicaldevice 10. Tabs 72 comprising suture locations 38 extend beyond theperimeter of the housing surface 47A providing locations to which asuture can be conveniently attached.

[0044]FIG. 10 illustrates a perspective view of another embodiment of aflexible member 101 that can be joined with the housing surface 32A ofmedical device 10. In this embodiment, the perimeter region 35 comprisessuture locations 38 and extends beyond the perimeter of the housingsurface 47A. As shown in FIGS. 9 and 10, both embodiments of theflexible member (91, 101) can be effectively attached to housing surface32A and efficiently mate with the perimeter 47A of the housing surface.When attached to the housing surface 32A, both embodiments (91 and 101)of the flexible member adhere to the entire housing surface 32A. Inother embodiments, this may not be required. Rather, the flexible membercan be shaped to adhere to only a portion of the housing surface. Thisis useful if it is necessary to stabilize only a portion of the medicaldevice.

[0045]FIG. 11 illustrates an asymmetrical embodiment of the invention.In particular, the perimeter region 35 extends further in the directionlabeled as “A” than in the other directions. Thus, the dimension of theperimeter region 35 of the flexible member 30 is larger in direction Athan in the other directions shown. This embodiment includes a pluralityof suture locations disposed in the perimeter region 35. The presence,location, and number of suture locations are determined by the needs andpreferences of the physician using the device.

[0046]FIG. 12 illustrates an embodiment of the flexible member 30comprising suture locations 38 disposed both in a perimeter region 35and on tabs 72. It is not necessary for all or any of the suturelocations 38 to be sutured by a physician. This embodiment alsoillustrates that more than one suture location 38 can be present on atab 72.

[0047]FIG. 13 illustrates an embodiment of the flexible member 30comprising a hole 131 in the center of the flexible member. Further, thesuture locations 38 are asymmetrically disposed about the perimeterregion 35 of the flexible member 30. This and other embodiments of aflexible member can be used to fulfill customized surgical requirements.

[0048]FIG. 14 illustrates a bottom view of an embodiment in which theflexible member 30 extends beyond the perimeter of the housing surface47 at two areas, labeled as X′ and X″ on the figure. Suture locations 38are present at perimeter regions 35′ and 35″. As shown, portions of thehousing surface 32 are not in contact with the flexible member 30. Aphysician can also use this embodiment to meet varying surgicalrequirements and preferences. For example, in this embodiment exposedhousing surfaces 142 and 143 are not in contact with flexible member 30.Thus, a physician can grasp these surfaces directly and use them tomanipulate the medical device during implantation of the medical deviceinto a body. The desirability and utilization of this and other specificembodiments of the invention varies widely among physicians.

[0049] FIGS. 15-18 illustrate various thickness characteristics of theflexible member 30 of the invention. Each of these embodiments caninclude tabs 72 and perimeter regions 35. In FIG. 15, the thickness ofthe flexible member 30 varies along its length. The medical device 10 isillustrated as being surgically positioned between a cutaneous layer 151and a tissue layer 154. The flexible member 30 includes a region ofincreased thickness 156 and a region of lower thickness 157. The varyingthickness of the flexible member allows it to fit snugly between thesurface of the housing 32 and the tissue layer 154. As shown, thecontour of the second surface 44 of the flexible member is shaped toconform to the shape of the tissue layer 154. Although the first surface41 of the flexible member can also be contoured, this is not necessaryin all embodiments.

[0050]FIG. 16 illustrates a flexible member 30 having a non-uniformvariation in its thickness. Thickness variations such as these are usedto match the shape of muscle, other tissue found within the body, andthe like. This feature can used to improve the placement stability ofthe medical device within a body.

[0051]FIG. 17 illustrates a bottom view of yet another embodiment inwhich the second surface of the flexible member 44 comprises ridges 171for stabilizing placement of the medical device 10. Ridges such as theseare useful for preventing longitudinal motion of the flexible memberwhen in contact with the body tissue.

[0052] Referring to FIG. 18, the shape of the flexible member can bepreformed to mate with a perimeter of the medical device. The flexiblemember 30 comprises extensions 182 that are formed to mate with thesurface of the housing 32, and are positioned at points about theperimeter 47 of the housing surface. In one embodiment, these extensions182 form a continuous ridge on the first surface 41 of the flexiblemember, encircling the perimeter 47 of housing surface 32 andfacilitating accurate alignment with the housing 11. The first surface41 can be coated with an adhesive to facilitate attachment to thesurface of the housing 32.

[0053]FIGS. 19 and 20 illustrate embodiments comprising a second surface44 of the flexible member with different textures. These textures caninclude, for example, bumps or hair-like tentacles. These textures canbe unidirectional (as shown in FIG. 20) or can be oriented in multipledirections. Textures can be formed as an integral part of the flexiblemember, or they can be attached to a surface of the flexible memberafter it has been formed. Although FIGS. 19 and 20 show the entiresecond surface 44 of the flexible member covered with a texture, in someembodiments only a portion of the second surface 44 is covered.Moreover, combinations of the different types of textures can be used onthe same flexible member. The first surface 41 of the flexible membercan also have a texture, although a smooth surface is generallypreferred to promote more effective adhesion with the housing surface32.

[0054] The suture locations 38 can be an important element of someembodiments of the invention. In one embodiment, the suture locations 38comprise permeable portions of the perimeter region 35 of the flexiblemember 30, such as a permeable membrane. For example, the suturelocations in each of the embodiments described above comprising aperimeter region 35 can have one or more suture locations 38 including apermeable membrane. A permeable membrane is any biocompatible materialthat a physician can penetrate with a suture needle, either before orduring implantation of the medical device within the body of a patient.A perimeter region 35 can comprise zero, one, or a plurality, of suturelocations. Furthermore, in some embodiments the entire perimeter region35 can be penetrable by a suture needle, and thus can function as alarge suture location 38. In still other embodiments, the entireflexible member 30 can be penetrable by a suture needle.

[0055] For embodiments comprising a permeable membrane, the suturelocation 38 is generally made of a material that closes back about thesuture or suture needle after the material has been penetrated. Suturelocations such as these can be penetrated one time or multiple times bya suture needle. Generally, a physician penetrates a given point withina suture location only once with a suture needle, although the samepoint on a suture location can be penetrated multiple times. However, asuture location can readily be sutured multiple times by a physician ifmultiple sutures are to be attached to that suture location, and thesesutures can be positioned at the same or different points. The suturelocation thus comprises a permeable membrane that can be penetrated atmultiple different locations. Multiple sutures can thus be locatedadjacent to each other, can be scattered about the suture location 38,or can be scattered about the perimeter region 35, all at the discretionof the physician. This is a useful feature in that a physician does nothave to determine before surgery if, or how many, sutures are needed, orprecisely at what locations about the medical device 10 they will beplaced.

[0056] The decision to attach any sutures to the medical device at allis at the discretion of the physician. Stabilization of the placement ofthe medical device 10 within a body using the flexible member 30,without suturing, and either with or without the presence of suturelocations, represents a preferred embodiment for some physicians.

[0057] In other embodiments, suture holes 14 may be punched into suturelocations 38. Suture locations 38 in each of the embodiments describedabove can have one or more suture holes 14. The use of suture holes 14eliminates the need for a physician to force a suture needle through thematerial of the suture location 38. More than one hole may be located ina suture location, and suture holes can be conveniently punched into theflexible member 30 before surgery using simple tools. Alternatively,suture holes 14 can be preformed at suture locations 38 about theperimeter region 35 of flexible member 30 at the time of manufacture.

[0058] In some embodiments prepunched patterns are formed, for example,in the perimeter region 35 or on the tabs 72 of the flexible member 30to facilitate the creation of suture holes 14. Holes prepunched in thismanner each have an easily removable plug, the removal of which createssuture holes 14 ready for use by a physician.

[0059] Although reference to sutures, suturing, and suture needles hasbeen made above, the invention is equally applicable to staples, hooks,and other devices and means known to those of skill in the art forplacing, securing, or attaching devices within a body. Use of the termssuture and suturing is intended to include these other devices andmethods.

[0060] Furthermore, the above discussion has centered on suturelocations 38 disposed within the perimeter region 35 specifically, andgenerally within the flexible member 30. However, the invention alsoincludes suture locations 38 disposed within tabs 72, as discussedabove. These suture locations can include suture holes 14, or not. Aswith the flexible member 30 and the flexible region 35, these tabs arepreferably foldable and flexible.

[0061] In embodiments, the suture holes 14 can be filled with a fillingmaterial. This filling material can be added to the suture hole 14before surgery, and preferably during manufacture of the flexible member30. The filling material should be formed of a soft material such assilicone that can be penetrated by a suture needle, and that will closeabout a suture after suturing. Other materials can be used to fill thesuture holes 14, such as CORETHANE® (registered mark of CorvitaCorporation, Miami, Fla.), polyurethane, and bionate polycarbonateurethanes. Materials with a Durometer reading of 50-55 are preferred forthis purpose. Such materials are relatively soft, and can beconveniently punctured with a needle. An appropriate material thicknessshould be used, as is apparent to one of ordinary skill in the art. Thesuture holes 14 can be filled or prefilled with the filling material.The presence of the filling material in the suture hole 14 minimizestissue ingrowth into the suture hole, making subsequent removal of themedical device less difficult.

[0062] Additionally the flexible member 30, and the medical device, canbe coated with a material, for example, to inhibit tissue ingrowth.Suitable coatings include but are not limited to antimicrobial coatingsfor the prevention of microbial biofilming, hydrogel coatings, zincoxide coatings for preventing surface irritation, various blockcopolymers, tackifying resins, and polybutene. The medical device andthe flexible member can also be impregnated with an antimicrobialsubstance, preferably at least in a portion of the device that will belocated near the cutaneous layer 151.

[0063]FIG. 21 is a flow chart illustrating steps that can be used tomanufacture a flexible member. First the desired shape, thickness,contours, and textures of the flexible member are determined (step 211).The locations of all the desired suture locations 38 are next determined(step 212). Which suture locations 38 will comprise tabs 72 and whichwill comprise perimeter regions 35 is next determined. Since tabs caneasily be removed later, additional tabs can be included that perhapsmight not be used during implantation of the device. A pattern can becreated for the flexible member (step 214) and a suitable polymer sheetselected (step 215). Preferably, the thickness regions 156, 157,extensions 182, surface textures, and contours of the flexible memberare achieved by selecting a polymer sheet possessing the desiredcharacteristics.

[0064] A shape corresponding to the pattern can then be cut from apolymer sheet (step 216), such as silicone. Any pre-planned suture holes14 can next be added to the tabs 72 and the perimeter regions 35 (step217). These can be added, for example, by puncturing. Optionally, anysuture holes 14 that have been formed in step 217 can be filled with asubstance to inhibit tissue growth into the suture hole (step 218).Finally, at the discretion of the physician, additional suture holes canbe added to suture locations 38 and any unwanted tabs 72 can be severedfrom the flexible member, at the time of surgery (step 219).

[0065] To complete the manufacture of a medical device, a housing, suchas that of an implantable port, is provided. The flexible member is thenattached to a surface of the medical device. When implanted within thebody, the medical device exhibits improved placement stability.

[0066] Other embodiments of the manufacturing process are also possible.For example, an adhesive coating can be applied to the flexible memberafter it has been cut from the polymer sheet, or the polymer sheet cancomprise an adhesive material before the cutting is performed.Preferably, the adhesive is applied to the sheet of polymer material byat least one of slot coating, spiral spraying, melt blowing, patterncoating, layering, dipping/drying, and ion deposition.

[0067] Suitable biocompatible adhesives are known to those of ordinaryskill in the art, and include water-based adhesives,methoxy-perfluoropropane, and thixotropic sealants. Such adhesives canbe coated continuously or discontinuously, and are compatible withmuscle, tissue, skin surfaces, and the like. The first surface 41 of theflexible member comprises such an adhesive, for contacting the housingsurface 32. Optionally, the same or a different adhesive can be appliedto the second surface 44 of the flexible member, for contacting tissuelayer 154. Tissue-specific adhesives can also be used. The applicationof adhesive to the second surface 44 of the flexible member contributesto the placement stabilization of the medical device 10. Adhesives oflow or moderate tacking strength can also be used on either surface, tofacilitate repositioning or removal of the flexible member. Preferably,the adhesive selected for this purpose will not leave a residue orexhibit any adhesive transfer to the tissue surface 154 upon removal orrelocation of the medical device 10. Materials left behind after removalof the medical device can adversely affect healing of the body.

[0068] The flexible member 30 can be manufactured from many differentmaterials. Preferably, the flexible member is formed from at least oneof thermoplastics, elastomers, polyurethanes, and fiber reinforcedelastomers. Suitable fibers for this purpose include polyester orKevlar® fiber. Kevlar® is a registered trademark of E. I. duPont deNemours and Company. The flexible member can also be manufactured frommaterials such as a latex/plastic polymer blend, silicone, vinyl, foam,rubbers, varying percentages of rubbery block co-polymers and midblockscomprising ethylene/propylene and ethylene/butylene, and mixturesthereof, S-EP block co-polymers (styrene-ethylene/propylene),dycyclopentadiene, fully hydrogenated aliphatic C5 and C9 resins, andalpha-methylstyrene based resins.

[0069] Various packaging and usage options are within the scope of theinvention. For example, a package can be sold that includes a set ofpre-cut flexible members or “frames.” The physician can then select thedesired style from the set, attach it to the medical device, and performthe implantation. The package can include flexible members with, forexample, a one, two, or three-hole option. The physician merely selectsthe flexible member that meets his needs and preferences. Optionally, ifdesired, the medical device can be trimmed and/or suture holes can beadded, before attaching a flexible member.

[0070]FIG. 22 is a flow chart illustrating steps that can be used by aphysician to select and prepare the flexible member for use. A physicianopens a package containing a number of flexible members (step 221). Oneof the flexible members from the package is selected. The flexiblemember selected should have tabs 72 and perimeter regions 35 in at leasteach of the locations desired (step 222). Extra, unwanted tabs can beremoved by cutting (step 223). Any additional suture holes 14 can beadded (step 224), for example, by puncturing. Optionally, a fillingmaterial such as silicone can be added to any suture holes that have notbeen prefilled, to prevent or minimize tissue ingrowth. These unfilledsuture holes can be filled by the physician or his staff before surgery,or after implantation into the body of a patient (described below). Theunfilled suture holes could have been formed, for example, in eitherstep 224 or step 217.

[0071]FIG. 23 is a flow chart illustrating steps that can be used toimplant and secure a medical device 10 comprising a flexible member 30into a body. Various methods can be used for this purpose. The physicianfirst determines the location and number of suture locations desired andprepares the flexible member as described in FIG. 22 (step 231). If theflexible member has tabs 72, any undesired tabs are removed. Ifinsufficient suture holes 14 are present, more can be added bypuncturing the appropriate suture location(s) of the flexible member.More than one suture hole can be added to each suture location,depending upon the physician's preference.

[0072] A linear incision is made in the patient (step 232). The incisionis of reduced size, due to the planned usage of the flexible member. Theflexible member can be adhesively attached to the housing surface 32 atthis time (step 233), or it can be attached later. Attaching it laterallows the smallest incision size to be used.

[0073] The housing 11 and the flexible member 30 are inserted throughthe incision, into the body of the patient, near an area in which thecatheter 22 is to be placed. The physician positions the catheter, andthen positions the flexible member adjacent the tissue layer 154 (step236). The flexible member is then sutured into place (step 237). Thiscan be done by sewing subcutaneous sutures through the suture locations38, thereby securing the flexible member 30 to adjacent tissue. Theflexible member is now attached to the housing surface 32, if it has notalready been attached (step 238). The incision is then closed andbandaged (step 239).

[0074] The sutures can thus be used to anchor the tissue layer 154and/or the cutaneous layer 151 to the medical device 10. In otherembodiments tissue can be anchored the medical device using subcutaneoushooks and other devices and methods known to the skilled artisan.

[0075] In some embodiments the flexible member 30 or the housing 11 canbe coated with materials that promote tissue growth to provide bettersealing of the incision, such as collagen or other tissue growthcatalysts and substances. Materials that promote ingrowth of cells, suchas a permeable fabric, a textured polymer, or appropriate mesh materialscan also be bonded to or embedded into the surface of medical device 10.The added ingrowth materials cause the skin surrounding the medicaldevice 10 to bond securely with the medical device 10. Alternatively,growth inhibition materials can be placed on or around the medicaldevice. For example, suture holes 14 that will not be used can be filledwith silicone to prevent tissue ingrowth. Thus, fibrin will not growinto these suture locations, and the medical device can later be moreeasily removed.

[0076] The flexible member of the invention is suitable for use withvarious medical devices including implantable venous ports, PEG ports,and other epidermal and indwelling medical devices that, for example,provide access to the body or to vasculature. These include devices usedfor gastrointestinal feeding and metering, intervascular pumps, insulinpumps, drainage products (such as for draining an abscess), pacingproducts (such as pacemakers), and various catheters.

[0077] While the invention has been particularly shown and describedwith reference to specific preferred embodiments, it should beunderstood by those skilled in the art that various changes in form anddetail may be made therein without departing from the spirit and scopeof the invention as defined by the appended claims.

What is claimed is:
 1. An implantable medical device for percutaneousaccess to a body comprising: a housing defining an entry site for theadministration, withdrawal, or exchange of fluids with the body; and aflexible member attached to a surface of the housing to stabilizeplacement of the implantable medical device within the body.
 2. Theimplantable medical device of claim 1 wherein the flexible membercomprises an adhesive disposed on a first surface of the flexible memberfor secure attachment to the surface of the housing.
 3. The implantablemedical device of claim 1 wherein the flexible member comprises one ormore suture locations.
 4. The implantable medical device of claim 3wherein at least one suture location defines a suture hole.
 5. Theimplantable medical device of claim 4 wherein at least one suture holeis filled with a tissue growth substance that inhibits tissue growthwithin the body.
 6. The implantable medical device of claim 5 whereinthe substance comprises at least one of silicone and a biocompatiblepolymer.
 7. The implantable medical device of claim 5 wherein thesubstance is penetrable by a suture needle.
 8. The implantable medicaldevice of claim 1 wherein a perimeter region of the flexible member ispenetrable by a suture needle.
 9. The implantable medical device ofclaim 2 wherein the flexible member comprises at least one of apolyurethane, a thermoplastic, an elastomer, and a fiber reinforcedelastomer.
 10. The implantable medical device of claim 2 wherein theflexible member comprises one or more tabs.
 11. The implantable medicaldevice of claim 10 wherein one or more of the tabs are located about aperimeter of the flexible member.
 12. The implantable medical device ofclaim 10 wherein at least one tab comprises a material penetrable by asuture needle.
 13. The implantable medical device of claim 10 whereinone or more tabs define one or more suture holes.
 14. The implantablemedical device of claim 1 wherein the flexible member is coated with amaterial that affects tissue growth within the body.
 15. The implantablemedical device of claim 1 wherein the flexible member is shaped toconform to tissue within the body.
 16. The implantable medical device ofclaim 1 wherein the flexible member is textured to conform to tissuewithin the body.
 17. The implantable medical device of claim 15 whereina second surface of the flexible member comprises an adhesive.
 18. Theimplantable medical device of claim 1 wherein the flexible member ispreformed to mate with the surface of the housing.
 19. The implantablemedical device of claim 18 wherein a portion of the flexible membercomprises a perimeter region surrounding at least a part of a perimeterof the housing.
 20. A flexible member for stabilizing the placement ofan implantable medical device within a body, comprising: a flexiblesubstrate shaped to mate with a surface of the medical device; one ormore suture locations formed on the flexible substrate; and an adhesivelocated on a first surface of the flexible substrate for secureattachment of the flexible substrate to the surface of the medicaldevice.
 21. The flexible member of claim 20 wherein the flexible membercomprises a material penetrable by a suture needle.
 22. The medicaldevice of claim 20 wherein the flexible member comprises at least one ofa polyurethane, a thermoplastic, an elastomer, and a fiber reinforcedelastomer.
 23. The flexible member of claim 20 further comprising one ormore suture locations.
 24. The flexible member of claim 23 wherein atleast one suture location defines a suture hole.
 25. The flexible memberof claim 24 wherein at least one suture hole is filled with a tissuegrowth substance that inhibits tissue growth within the body.
 26. Theflexible member of claim 25 wherein the substance comprises at lease oneof silicone and a biocompatible polymer.
 27. The flexible member ofclaim 26 wherein the substance is penetrable by a suture needle.
 28. Theflexible member of claim 20 further comprising one or more tabs.
 29. Theflexible member of claim 28 wherein one or more of the tabs is disposedabout a perimeter of the flexible member.
 30. The flexible member ofclaim 28 wherein the one or more tabs are flexible.
 31. The flexiblemember of claim 28 wherein at least one tab comprises a materialpenetrable by a suture needle.
 32. The flexible member of claim 20further comprising a coating to inhibit tissue growth.
 33. The flexiblemember of claim 20 wherein a shape of the flexible member is preformedto mate with a perimeter of the medical device.
 34. The flexible memberof claim 33 wherein a second surface of the flexible member is shaped toconform to tissue within the body.
 35. The flexible member of claim 20wherein at least a portion of a perimeter of the flexible member followsa perimeter of the surface of the medical device to which the flexiblemember is to be attached.
 36. The flexible member of claim 20 whereinthe adhesive comprises at least one of methoxy-perfluoropropane,thixotropic sealants, and water-based adhesives.
 37. A method ofmanufacturing an implantable medical device for percutaneous access to abody, comprising: providing a housing defining an entry site for theadministration, withdrawal, or exchange of fluids with the body; andattaching a flexible member to a surface of the housing to stabilizeplacement of the implantable medical device within the body.
 38. Themethod of claim 37 further comprising: applying adhesive to the flexiblemember by at least one of spray coating, slot coating, spiral spraying,melt-blowing, pattern coating, layering, dipping and drying, and iondeposition.
 39. The method of claim 37 further comprising: forming theflexible member by cutting from a sheet of silicone polymer.
 40. Amethod of fabricating a flexible member for attachment to an implantablemedical device for percutaneous access to a body, comprising: forming ashape for mating with an implantable medical device; forming suturelocations about the shape of flexible member; and applying an adhesiveto the shape of the flexible member.
 41. The method of claim 40 whereinforming a shape further comprises cutting from a sheet of siliconepolymer.
 42. The method of claim 40 further comprising forming sutureholes in the flexible member.